JP3490846B2 - Double-sided recording disk - Google Patents

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a double-sided recording disk having recording layers on both sides.

[0002]

2. Description of the Related Art Conventionally, MO discs (magneto-optical discs) and DVDs (digital video discs) are widely known as recording discs having recording layers on both front and back surfaces. This type of recording disc, for example,
It is formed by laminating a pair of disks as follows. The disk has a protective film made of hard resin,
The recording layer is formed on the surface of the protective film, and the transparent substrate is provided on the surface of the recording layer. The recording layer is, for example, a reflecting layer formed of a thin film layer of aluminum, and the surface of the reflecting layer. And an uneven layer (the unevenness of the uneven layer corresponds to the recorded information). And
The concavo-convex layer of the recording layer may be formed integrally with the transparent substrate, for example. The pair of discs are laminated so that the protective films face each other, and the recording disc formed by this has transparent substrates on both sides thereof.

This type of recording disk is used by being housed in a cartridge as shown in FIG. 9, for example. The conventional cartridge includes a cartridge body 2 in the shape of a thin rectangular box, and an opening 4 (only one of which is shown in FIG. 9) is formed at a predetermined position on both sides of the cartridge body 2.
An open / close cover 6 for opening / closing is attached so as to be openable / closable.
The opening / closing cover 6 is moved in the opening direction by mounting the cartridge main body 2 on the disk drive device to open the opening 4. On both sides of the cartridge body 2,
A symbol for displaying the recording surface (either the front surface or the back surface) of the accommodated recording disk 8 is attached, for example, “A” for displaying the front surface or “B” for displaying the back surface. For example, when the surface marked with the symbol "A" is mounted on the drive device with the surface facing upward, the information recorded in the recording layer on the surface of the recording disk corresponding to the symbol "A" is read out or recorded in this recording layer. Information can be recorded.

[0004]

In this type of recording disk, when the cartridge body 2 is always housed and used, since the recording surface is indicated on the cartridge body 2, this indication is displayed. The recording surface of the recording disk 8 accommodated can be identified by looking at it.
However, when the recording disk 8 is removed from the cartridge body 2 for storage, or when the recording disk 8 is used without being housed in the cartridge body 2, it is quite difficult to identify the front and back sides of the recording disk alone.

Therefore, in order to identify the front and back of the recording disk, a recording disk in which the front or back surface of the disk main body is colored has been proposed, as disclosed in, for example, Japanese Patent Application Laid-Open No. 7-235083. Since this recording disk is colored, the front surface and the back surface can be easily identified, but a process for coloring the front surface and / or the back surface of the recording disk is required, and its production There is a problem that the process becomes complicated.

An object of the present invention is to provide a double-sided recording disk which can be manufactured relatively easily and whose front and back surfaces can be easily identified.

[0007]

[0008]

[0009]

[0010]

DISCLOSURE OF THE INVENTION The present invention is a disc body composed of a pair of discs each having a recording layer on which recording information is recorded and a transparent substrate covering the recording layer. One of the outer shapes is circular, and the other outer shape is polygonal. A pair of discs are laminated so that their transparent substrates are located on the front surface side of the disc body. It is a double-sided recording disk. According to the present invention, the outer diameter of one disc is circular and the outer diameter of the other disc is polygonal. Therefore, the outer diameter of the other disc may be changed from that of the conventional disc. Can be visually identified.

[0011]

Further, the present invention is a disc main body composed of a pair of discs having a recording layer on which recording information is recorded and a transparent substrate covering the recording layer, wherein one outer peripheral surface of the pair of discs is It is a disc body formed by laminating the pair of discs, which are flat and the other outer peripheral surface of which is provided with knurled irregularities, so that their transparent substrates are located on the surface side of the disc body. It is a characteristic double-sided recording disk. According to the invention,
Since the outer peripheral surface of one disk is flat and the outer peripheral surface of the other disk is formed with knurled irregularities,
The outer peripheral surface of the other disk may be changed from that of the conventional one, whereby the surface of the recording disk can be visually identified.

[0013]

[0014]

Further, the present invention is a disc main body composed of a pair of discs having a recording layer on which recording information is recorded and a transparent substrate covering the recording layer, wherein the inner peripheral portion of the disc has a circular shape. Of the pair of discs, one of the pair of discs having a flat non-recording region and the other non-recording region provided with irregularities of a satin pattern, the transparent substrate of which is the disc body. A double-sided recording disk, which is a disk body formed by being stuck so as to be located on the front surface side of the disk. According to the invention,
Since the non-recording area on one side of the disc body is flat and the non-recording area on the other side is provided with small textured patterns, the difference in appearance of this non-recording area is used to visualize the surface of the recording disc. Can be identified by.

[0016]

[0017]

[0018]

[0019]

[0020]

1 is a perspective view showing the basic structure of a double-sided recording disk according to the present invention. In FIG. 1, the illustrated recording disk 20 is composed of a disk body 23 formed by bonding two disks 22 and 24 together, and a circular through hole 25 is formed in the center of the disk body 23. There is. The disks 22 and 24 have substantially the same structure, and as shown in an enlarged view in FIG. 2, a protective film 21 made of a hard resin, a recording layer 27 formed on the surface of the protective film 21, and the recording layer The recording layer 27 includes a transparent substrate 28 provided on the surface of the recording layer 27, and the recording layer 27 includes a reflective layer 29 formed of an aluminum thin film layer and the transparent substrate 2.
8 is a concavo-convex portion 31 integrally formed on the surface of the reflective layer 29 of FIG.
(In the case of a read-only disc, the unevenness of the uneven portion corresponds to the recorded information). In the case of a recordable disc, the reflective layer 29 and the surface of the reflective layer 29 (the transparent substrate 28) are included.
A magneto-optical film or the like (not shown) provided on the side) is included. The pair of disks 22 and 24 are laminated so that the protective films 21 face each other, and the recording disk 20 thus formed has transparent substrates 28 on both sides thereof.

In order to identify the front and back sides of the double-sided recording disk, for example, the transparent substrate 28 of one of the disks 22 (the disk located on the upper side in FIG. 1) is formed by molding a commonly used polycarbonate resin. On the other hand, the transparent substrate 28 of the other disc 24 (the disc located on the lower side in FIG. 1) is made of the above-mentioned polycarbonate resin by Nippon Pigment Co., Ltd.
B-J6485D (see Japanese Patent Application Laid-Open No. 7-262606) has a color material of 0.00
It is formed by molding with 1% attached.

In the recording disc 20 formed by laminating the discs 22 and 24 as described above, the disc 2
The transparent substrate 28 that covers the second recording layer 27 is colorless, whereas the transparent substrate 28 that covers the recording layer 27 of the disk 24.
Contains a coloring material and is colored in a specific color. Therefore, by discriminating the color of the surface of the recording disk 20, it is possible to easily identify the surface of the recording disk 20, for example, the colorless surface or the back surface thereof, for example, the colored surface.

Further, in this embodiment, the colorless resin is used when the transparent substrate 28 of the disk 22 is formed, and the colored resin is used when the transparent substrate 28 of the other disk 24 is formed. The recording disk 20 without the need for a step for providing a means.
Face can be identified. The uncolored resin may be the one that has been conventionally used.

[0024]

[0025]

FIG. 3 is a perspective view showing a first general form of a recording disk. In the first mode, the outer shapes of the pair of disks are different from each other. In FIG.
The illustrated recording disk 30 is composed of two disks 32, 34.
Disk body 36 formed by laminating
It consists of Each of the disks 32 and 34 has substantially the same structure as the disks 22 and 24 of the first embodiment, and their bonding is performed in the same manner as in the first embodiment.

In this embodiment, the outer shape of the disk 32 and the outer shape of the other disk 34 are different from each other.
That is, the disc 32 located on the upper side in FIG.
Is cut out in a straight line in a part of the outer shape that is substantially circular,
As a result, the cutout portion 38 is formed. The notch 38 is for identifying the disc 32,
Therefore, the shape may be any shape that can be visually identified. On the other hand, the outer shape of the disk 34 located on the lower side in FIG. 3 is substantially circular. This shape of the disks 32, 34 can be formed, for example, by using a stamper press with a correspondingly shaped mold, and conventional disks 34 can be used.

[0028]

[0029]

[0030]

FIG. 4 is a perspective view showing a first embodiment of the recording disk of the present invention. In the first embodiment, the outer shapes of the disks to be bonded to each other are different. In FIG. 4, the recording disk 40 shown in the drawing is composed of a disk body 46 formed by bonding two disks 42 and 44 together. Each disc 4
2, 44 may have substantially the same structure as the disks 32, 34, and the bonding thereof can be performed in the same manner as described above. In this configuration, the upper disc 42 is
For example, the disk 44 located on the lower side has a substantially circular outer shape, while the outer shape of the disk has a regular 24-sided outer shape. Therefore, by discriminating the outer shape of the upper part and the outer shape of the lower part of the recording disk 40, the surface of the recording disk 40, for example, the surface on the regular 24 side, or the back surface thereof,
For example, it can be easily identified whether it is a circular surface. Visual identification is assured for the first general form.

In the first embodiment, the disk 4
Although the outer shape of 2 is formed into a regular 24-sided shape, the shape is not limited to this and may be a polygonal shape other than a circular shape.

FIG. 5 is a perspective view showing a second embodiment of the recording disk of the present invention. In the second embodiment, the shape of the outer peripheral surface of the recording disk is different. Figure 5
In the figure, the illustrated recording disk 50 is composed of a disk body 56 formed by bonding two disks 52 and 54 together. Each disk 52, 54
May have substantially the same configuration as the disks 22 and 24 of the first embodiment, and the bonding can be performed in the same manner as described above. In this form, the disk 52 located on the upper side has a circular outer peripheral surface, and on the outer peripheral surface, small irregularities 58 in a knurled pattern are provided substantially all around. On the other hand, the disk 54 located on the lower side also has a substantially circular outer shape, but its outer peripheral surface is substantially flat. Therefore, by discriminating the upper outer peripheral surface and the lower outer peripheral surface of the recording disk 50,
It is possible to easily discriminate between the front surface, for example, the surface side having a knurled pattern, or the back surface, for example, the flat surface side. The discs 52 and 54 can be formed in the same manner as the discs 32 and 34 in the first embodiment, for example.

In the second embodiment, the knurl pattern is applied to the entire outer peripheral surface of the disk 52, but the present invention is not limited to this, and the knurl pattern may be applied only to a part of the outer peripheral surface. Good.

FIG. 6 is a perspective view showing a second general form of a double-sided recording disk. In this form, the structure of the non-recording area of the recording disk is different. In FIG. 6, the recording disk 60 shown in FIG.
The disk main body 66 is formed by laminating the two and 64 together. Each disk 62, 64
May have substantially the same configuration as the disks 22 and 24 of the first embodiment, and the bonding can be performed in the same manner as described above. As shown in FIG. 6, the disk 62 has an outer non-recording area 68 on the outer periphery thereof, an inner non-recording area 70 on the inner periphery thereof, and an outer non-recording area 68 and an inner non-recording area 68. A recording area 72 exists between the area 70 and the area 70. A recording layer exists in the recording area 72 and therefore information can be recorded, but in the non-recording areas 68 and 70 there is substantially no recording layer and therefore information cannot be recorded. The other disc 64 is also disc 62
Although not shown, it has an outer non-recording area, a recording area, and an inner non-recording area. The recording disk 2 of the first to third embodiments
0, 40, 50 are also disks 30 of the first general form.
Although not particularly described, similarly to the recording disk 60 of the second general form, it has an outer non-recording area, a recording area and an inner non-recording area on both sides thereof.

In this embodiment, the disc 6 located on the upper side
In No. 2, four circular recesses 74 are provided at intervals in the circumferential direction in the non-recording area 70 inside the circular shape. On the other hand, such a recess 74 is not provided in the non-recording area of the disc 64 located on the lower side. Therefore, the recording disk 6 is determined by determining whether or not the configuration of the non-recording area 70 on one surface (for example, the front surface) and the other surface (for example, the rear surface) of the recording disk 60, that is, whether or not the recess 74 exists.
It is possible to distinguish whether it is the front surface of 0, for example, the surface having the concave portion 74, or the rear surface thereof, for example, the flat surface without the concave portion 74. Such a disc 62 can be formed by using, for example, a molding die having a mold portion corresponding to the shape of the recess 74, and a conventional disc 64 can be used.

In this embodiment, when the transparent substrate of the disk 62 is formed, the recess 74 is formed in the non-recording area 70, and the other disk 64 is formed in the conventional manner, so that a step for providing the identifying means is required. The surface of the recording disc 60 can be identified without

In this embodiment, a pair of disks 62, 64
Although the recording disk 60 is formed by adhering the above, the recording disk 60 can also be formed by sequentially forming various layers.

[0039]

FIG. 7 is a perspective view showing a recording disk of a third general form. In FIG. 7, the illustrated recording disk 80 is composed of a disk body 86 formed by bonding two disks 82 and 84 together. Each of the disks 82 and 84 may have substantially the same configuration as that of the second embodiment, and the bonding thereof may be the same. The disks 82 and 84 are arranged from the outer side to the inner side in the radial direction so that the outer non-recording area 88, the recording area 90, and the inner non-recording area 9 are formed.
2 (only the disk 82 is shown in FIG. 7).

In this embodiment, the disk 8 located on the upper side
No. 2 is a circular non-recording area 92 on the inner side of the disk 84, for example, a symbol "A" indicating the surface is given to the non-recording area 92 on the inner side, and a circular non-recording area of the disc 84 located on the lower side although not shown. Has, for example, a symbol "B" indicating the back side. Therefore, by discriminating the symbols, that is, the display symbols “A” and “B”, applied to the non-recording area 92 on one side (for example, the front side) and the other side (for example, the back side) of the recording disc 80, the front side of the recording disc 80, for example, , The surface on which the display “A” is present or the back surface thereof, for example, the surface on which the display “B” is present can be easily identified. Such discs 82, 84 can be formed, for example, by using a mold having mold portions corresponding to the indications "A" and "B", respectively.

In this embodiment, the display "A" is displayed on the non-recording area 92 when the transparent substrate of the disk 82 is formed, and the display "B" is displayed on the non-recording area when the transparent substrate of the other disk 84 is formed. Is applied, and the surface of the recording disk 80 can be identified without requiring a special step for providing the identifying means.

Also in this form, the pair of disks 82, 84
It can be formed by sequentially forming various layers instead of laminating.

Further, in this embodiment, the displays "A" and "B" are used as the displays for distinguishing the front and back of the recording disk 80, but instead of this, for example, the displays "1" and "2", Or display "I" and "II"
Etc. are used.

FIG. 8 is a perspective view showing a recording disk according to the third embodiment of the present invention. Also in the third embodiment, the structures of the non-recording areas on both sides of the recording disk are different. In FIG. 8, the recording disk 100 shown in FIG.
It is composed of a disc body 106 formed by pasting together the discs 102 and 104. Each of the disks 102 and 104 may have substantially the same configuration as that of the sixth embodiment, and the pasting may be the same. In the same manner as described above, the disks 102 and 104 are arranged such that the outer non-recording area 108 and the recording area 11 extend from the outer side to the inner side in the radial direction.
It has 0 and an inner non-recording area 112 (in FIG. 8, only the disk 102 is shown).

In the third embodiment, the disc 102 located on the upper side has a circular inner non-recording area 70.
While the small unevenness due to the satin pattern 114 is provided over substantially the entire area of the
Although not shown in the drawing, the circular non-recording area does not have such a satin pattern and is formed on a flat surface. Therefore, the surface of the recording disk 100, for example, the surface having a satin pattern is determined by determining the presence of small unevenness on the non-recording area 112 on one surface (for example, the front surface) and the other surface (for example, the rear surface) of the recording disk 100. , Or its back surface, for example, a flat surface, can be easily identified. Such a disc 102 can be formed, for example, by using a forming die having a die portion corresponding to a satin pattern, and the other disc 104 can be formed by using a forming die which has been conventionally used. it can.

In this embodiment, when the transparent substrate of the disk 102 is formed, small unevenness due to a satin pattern is formed in the non-recording area 112, and the other disk 104 may be formed of a transparent substrate as in the conventional method. The surface of the recording disc 100 can be identified without the need for special steps to provide the means.

Also in the third embodiment, the pair of disks 1
It can be formed by sequentially forming various layers instead of laminating 02 and 104.

Further, in the third embodiment, the satin pattern 114 is applied to substantially the entire non-recording area 112 of the disk 102 of the recording disk 100, but the present invention is not limited to this, and the non-recording area is not limited thereto. The satin pattern may be applied only to a part of 112.

[0050]

[0051]

[0052]

[0053]

[0054]

According to the present invention, the outer diameter of one disk is circular and the outer diameter of the other disk is polygonal.
The outer diameter of the other disc can be changed from the conventional one,
This allows the surface of the recording disc to be visually identified.

[0055]

Further, according to the present invention, since the outer peripheral surface of one disk is flat and the outer peripheral surface of the other disk is formed with knurled irregularities, the outer peripheral surface of the other disk is different from the conventional one. It can be changed so that the surface of the recording disc can be visually identified.

[0057]

[0058]

Further, according to the present invention, the non-recording area on one side of the disk body is flat, and the non-recording area on the other side is provided with small unevenness in a satin pattern. Can be used to visually identify the surface of the recording disc.

[0060]

[0061]

[0062]

[0063]

[Brief description of drawings]

FIG. 1 is a perspective view showing the basic structure of a double-sided recording disk according to the present invention.

2 is a partially enlarged cross-sectional view showing a part of a one-sided disc that constitutes the recording disc of FIG.

FIG. 3 is a perspective view showing a first general form of a double-sided recording disk.

FIG. 4 is a perspective view showing a first embodiment of a double-sided recording disk according to the present invention.

FIG. 5 is a perspective view showing a second embodiment of a double-sided recording disk according to the present invention.

FIG. 6 is a perspective view showing a second general form of a double-sided recording disk.

FIG. 7 is a perspective view showing a third general form of a double-sided recording disk.

FIG. 8 is a perspective view showing a third embodiment of a double-sided recording disk according to the present invention.

FIG. 9 is a partially cutaway perspective view showing a conventional cartridge containing a double-sided recording disk with a part cut away.

[Explanation of symbols]

8, 20, 30, 40, 50, 60, 80, 100 Recording disk 21 Protective film 22, 32, 42, 52, 62, 82, 102 One disk 23, 36, 46, 56, 66, 86, 106 Disk Main body 24, 34, 44, 54, 64, 84, 104 Other disc 27 Recording layer 28 Transparent substrate 68, 88, 108 Outer non-recording area 70, 92, 112 Inner non-recording area 72, 90, 110 Recording area

─────────────────────────────────────────────────── ─── Continuation of front page (58) Fields surveyed (Int.Cl. ⁷ , DB name) G11B 7/24

Claims (3)

(57) [Claims] 1. A disc body comprising a pair of discs having a recording layer on which recording information is recorded and a transparent substrate covering the recording layer, wherein one outer shape of the pair of discs is circular and the other is the other. The double-sided recording disk is a disk body formed by laminating the pair of disks each having a polygonal outer shape so that their transparent substrates are located on the front surface side of the disk body. 2. A disc body comprising a recording layer on which recording information is recorded and a pair of discs having a transparent substrate covering the recording layer, wherein one outer peripheral surface of the pair of discs is flat. The other outer peripheral surface is a disc body formed by laminating the pair of discs provided with knurled irregularities so that their transparent substrates are located on the front side of the disc body. Double-sided recording disc. 3. A disc main body composed of a pair of discs having a recording layer on which recording information is recorded and a transparent substrate covering the recording layer, wherein a circular non-recording is provided on an inner peripheral portion of the disc. The pair of discs, one of which has a flat non-recording region and the other of which has a satin-patterned uneven surface, and the transparent substrate has a transparent substrate on the surface side of the disc body. A double-sided recording disk, which is a disk main body formed by being laminated so as to be located at.